187525domain: NAppears in sequencesa(n) = n*(n+1)*(n^2-2*n+2)/2.at n=25A101375Number of (n+1)X(n+1) 0..4 arrays with the array of 2X2 subblock determinants symmetric.at n=1A187456T(n,k)=Number of (n+1)X(n+1) 0..k arrays with the array of 2X2 subblock determinants symmetric.at n=11A187457